>>17829480
The universe literally cannot become immortal
First off, given enough time, every particle in the universe can undergo particle decay

Uranium 238 decays into Thorium 234 and Helium4. Because of their short halflifes, we can record this easily
But it is also believed that even something as stable as carbon or even Hydrogen itself could eventually decay into individual pockets of photons.

And photons itself can eventually decay into positron and electron. Thus leading into the Heat Death of the universe

If, however, photons do not decay, then, eventually, gravity would take over and cause quantum particles to eventually turn into individual packets of blackholes

Either way, the universe is not, and cannot be eternal

We are currently living at the perfect time in the universe
Not too energetic for radiation
Energetic enough to still watch new stars born
At the tail end of the Milky Way where the sky is dark enough to see it all
With a Sun that is easily the most stable star ever discovered